Airport Express Very, Very, Slow

Question

I have an iMac with a Airport Extreme router and an Airport Express being used as a wireless network extender.
The Extreme is connected to my Virgin broadband @ 29-30 meg and works fine. However on my next floor up where the Express is , not some 20 feet away it will not work above 2.5 meg and sometimes drops to below a meg.
I have been on many web sites to try and find why the Airport Express is so much slower but so far no luck and what I have noticed looking on the web is that I'm not the only one to have this problem and some of these complaints go back a couple of years and yet still no comment or solution from Apple.
I would be very grateful for any help .
Regards Jeff...

Answer 1

There are so many environmental variables that affect wireless networks that finding a solution to your problem can be elusive.
"Extending" a wireless network using an Express in the manner you describe essentially retransmits the same wireless signal it receives from the Extreme. If the Express is only capable of receiving a weak wireless signal, its signal may be strong but its throughput will be slow. The wireless signal it "extends" will be useful over the additional range provided by the Express but it will still be slow. To diagnose or confirm this possibility, unplug the Express and position a Mac in the exact same location. Whatever speed the Mac is capable of achieving will be similar for the Express.
Make sure the Macs you are using are connected to the Express vs. the Extreme. A Mac will not necessarily connect to the nearest access point, but if you position the Mac near the Express, turn off AirPort under its Wi-Fi icon, then turn it back on, it should connect to the Express.
If that test suggests the Express should be peforming better than it is, then investigate the wireless spectrum you are using. All new AirPort Base Stations are capable of creating and "extending" both 2.4 and 5 GHz networks. Generally speaking, 5 GHz is better due to its far greater number of available channels and less competition from neighboring wireless networks. Make sure the Express is configured to connect and "extend" the 5 GHz network and make sure the devices using it are also using 5 GHz.
If you are using 5 GHz, and the Express is in an area that receives a good wireless signal from the Extreme, and you are still observing poor performance, then there may be an internal parameter that has become corrupted in the Express. In that event a "hard reset" and subsequent reconfiguration is justified, followed by a repeat of the above tests.
If that fails to achieve any improvement, the possibility of a defective Express should be considered.
In the end a "roaming network" is a far more effective installation. It requires connecting the two with an Ethernet cable and a degree of labour that you may or may not wish to undertake yourself.